SONET: North American Standard for Digital Transmission

Synchronous Optical Network (SONET) is the standard of SDH in North America consisting of a set of graduate digital transmitting technologies.

Wavelength Division Multiplexing is one of the basic multiplexing techniques which can make the data rate and system capacity pair gained by means of transmitting various signals of different wavelengths into single fiber.

Being the integration of digital transmission network and digital bearer network, Integrated Services Digital Network(ISDN) can provide various kinds of voice and data services. With the basic rate interface(BRI) including two B channels of 64Kbps and a D channel of 16Kbps respectively, you can get the rate of 64Kbps if you chose a B channel of ISDN to connect to the Internet.

Electromagnetic Interference means the interference caused by the from electromagnetic waves, which can be divided into interference and interference.